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1.
Bionanoscience ; 12(2): 620-626, 2022.
Article En | MEDLINE | ID: mdl-35371905

The COVID-19 pandemic has dramatically changed existing norm perception both in medical practice and in society. In the context of limited resources and absence of a known treatment protocol, this change particularly affected healthcare system, doctors, and the distribution of a life-support therapy. One of the main bioethical dilemmas presented by coronavirus epidemic is the discrepancy between public health ethics, characterized by the fair distribution of limited resources and public safety orientation, and patient-specific clinical ethics. The COVID-19 pandemic forced health workers into tragic situations that they had never previously experienced, when lack of available health care workers, ventilators, or hospital beds creates a necessity to classify and prioritize patients to determine who will get (or will not get) what type of care and where. Another important issue is the digital control of citizens who must reduce their freedom for the sake of the health of other citizens. This caused great concern among many people, who fear that the current situation will lead to their manipulation in the future. There is also a question of responsibility among politicians and authorized organizations for the health of not only the population of their country, but also the entire planet. These and other current issues require bioethical expertise.

2.
Transl Psychiatry ; 6: e730, 2016 Feb 09.
Article En | MEDLINE | ID: mdl-26859813

Myalgic encephalomyelitis, also known as chronic fatigue syndrome or ME/CFS, is a multifactorial and debilitating disease that has an impact on over 4 million people in the United States alone. The pathogenesis of ME/CFS remains largely unknown; however, a genetic predisposition has been suggested. In the present study, we used a DNA single-nucleotide polymorphism (SNP) chip representing over 906,600 known SNPs to analyze DNA from ME/CFS subjects and healthy controls. To the best of our knowledge, this study represents the most comprehensive genome-wide association study (GWAS) of an ME/CFS cohort conducted to date. Here 442 SNPs were identified as candidates for association with ME/CFS (adjusted P-value<0.05). Whereas the majority of these SNPs are represented in non-coding regions of the genome, 12 SNPs were identified in the coding region of their respective gene. Among these, two candidate SNPs resulted in missense substitutions, one in a pattern recognition receptor and the other in an uncharacterized coiled-coil domain-containing protein. We also identified five SNPs that cluster in the non-coding regions of T-cell receptor loci. Further examination of these polymorphisms may help identify contributing factors to the pathophysiology of ME/CFS, as well as categorize potential targets for medical intervention strategies.


Fatigue Syndrome, Chronic/genetics , Genetic Variation/genetics , Genome-Wide Association Study/methods , Female , Genetic Predisposition to Disease/genetics , Humans , Male , Middle Aged , Pilot Projects , Polymorphism, Single Nucleotide
3.
Clin Exp Immunol ; 180(3): 520-30, 2015 Jun.
Article En | MEDLINE | ID: mdl-25619261

Citrate, a central component of cellular metabolism, is a widely used anti-coagulant due to its ability to chelate calcium. Adenosine triphosphate (ATP)-citrate lyase, which metabolizes citrate, has been shown to be essential for inflammation, but the ability of exogenous citrate to impact inflammatory signalling cascades remains largely unknown. We hypothesized that citrate would modulate inflammatory responses as both a cellular metabolite and calcium chelator, and tested this hypothesis by determining how clinically relevant levels of citrate modulate monocyte proinflammatory responses to lipopolysaccharide (LPS) in a human acute monocytic leukaemia cell line (THP-1). In normal medium (0.4 mM calcium), citrate inhibited LPS-induced tumour necrosis factor (TNF)-α and interleukin (IL)-8 transcripts, whereas in medium supplemented with calcium (1.4 mM), TNF-α and IL-8 levels increased and appeared independent of calcium chelation. Using an IL-8-luciferase plasmid construct, the same increased response was observed in the activation of the IL-8 promoter region, suggesting transcriptional regulation. Tricarballylic acid, an inhibitor of ATP-citrate lyase, blocked the ability of citrate to augment TNF-α, linking citrate's augmentation effect with its metabolism by ATP-citrate lyase. In the presence of citrate, increased histone acetylation was observed in the TNF-α and IL-8 promoter regions of THP-1 cells. We observed that citrate can both augment and inhibit proinflammatory cytokine production via modulation of inflammatory gene transactivation. These findings suggest that citrate anti-coagulation may alter immune function through complex interactions with the inflammatory response.


Citric Acid/metabolism , Inflammation/immunology , Inflammation/metabolism , Lipopolysaccharides/immunology , Monocytes/immunology , Monocytes/metabolism , Acetylation , Calcium/metabolism , Calcium/pharmacology , Cell Line, Tumor , Citric Acid/pharmacology , Gene Expression Regulation/drug effects , Histones/metabolism , Humans , Inflammation/genetics , Interleukin-8/genetics , Interleukin-8/metabolism , Monocytes/drug effects , Promoter Regions, Genetic , RNA, Messenger/genetics , Transcriptional Activation , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism
4.
Bioorg Med Chem ; 9(6): 1371-84, 2001 Jun.
Article En | MEDLINE | ID: mdl-11408158

Apoptosis is a complex biochemical process that involves all aspects of the cell from the plasma membrane to the nucleus. Apoptosis stimuli are mediated by many different cellular processes including protein synthesis and degradation, the alteration in protein phosphorylation states, the activation of lipid second messenger systems, and disruption of normal mitochondrial function. Despite this diversity in signal transduction, all apoptotic pathways are believed to converge ultimately with the activation of caspases leading to the characteristic morphological changes of apoptosis. In this review, we discuss what is known about these pathways and its implication for normal cellular function.


Apoptosis/physiology , Caspases/metabolism , Phosphoprotein Phosphatases/metabolism , Protein Kinases/metabolism , Signal Transduction , Animals , Cell Death/physiology , Ceramides/metabolism , Humans , Mitochondria/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , Tumor Suppressor Protein p53/metabolism
5.
Pharmacol Ther ; 83(2): 125-39, 1999 Aug.
Article En | MEDLINE | ID: mdl-10511458

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that affects most of the organs and tissues of the body, causing glomerulonephritis, arthritis, and cerebritis. SLE can be fatal with nephritis, in particular, predicting a poor outcome for patients. In this review, we highlight what has been learned about SLE from the study of mouse models, and pay particular attention to anti-DNA autoantibodies, both as pathological agents of lupus nephritis and as DNA-binding proteins. We summarize the current approaches used to treat SLE and discuss the targeting of anti-DNA autoantibodies as a new treatment for lupus nephritis.


Antibodies, Antinuclear/immunology , Lupus Erythematosus, Systemic/drug therapy , Lupus Erythematosus, Systemic/etiology , Animals , Antibodies, Antinuclear/therapeutic use , Clinical Trials as Topic , Cross Reactions , DNA Adducts , Disease Models, Animal , Forecasting , Humans , Lupus Erythematosus, Systemic/pathology , Mice , Proteins/metabolism
6.
Hybridoma ; 17(1): 33-9, 1998 Feb.
Article En | MEDLINE | ID: mdl-9523235

We have previously described the isolation and in vitro binding properties of eight anti-DNA monoclonal antibodies (MAbs) from an MRL-lpr mouse. In light of recent reports that have indicated it is possible to isolate multiple MAbs from a single hybridoma, our pathogenic hybridoma, 11F8, was examined for evidence of similar phenomena. Chromosome counting suggested that 11F8 cells are unusual and might indeed be expressing multiple heavy and/or light chains. PCR, cloning, and sequencing of immunoglobulin heavy and light chains indicate that 11F8 displays expression of both gamma 2a and gamma 3 heavy chains at the DNA level. Flow cytometry and amino acid sequencing reveals that expression of multiple isotypes also occurs at the protein level but only a single heavy- and light-chain sequence is able to bind DNA. Based on these results, we conclude that 11F8 is an unusual hybridoma that secretes two distinct heavy and at least one light chain from a single cell, and may represent a trioma, a stable three-cell fusion.


DNA/immunology , Hybridomas/immunology , Immunoglobulins/immunology , Mice, Inbred MRL lpr/immunology , Amino Acid Sequence , Animals , Antibodies, Monoclonal/immunology , Base Sequence , Cloning, Molecular , Immunoglobulin Heavy Chains/genetics , Immunoglobulin Heavy Chains/immunology , Immunoglobulin Light Chains/genetics , Immunoglobulin Light Chains/immunology , Immunoglobulins/genetics , Karyotyping , Mice , Molecular Sequence Data , Sequence Analysis, DNA
8.
J Clin Invest ; 97(7): 1748-60, 1996 Apr 01.
Article En | MEDLINE | ID: mdl-8601641

Although anti-DNA autoantibodies are an important hallmark of lupus, the relationships among anti-DNA structure, reactivity, and pathogenicity have not been fully elucidated. To further investigate these relationships, we compare the variable genes and primary structure of eight anti-DNA mAbs previously obtained from an MRL/MpJ-lpr/lpr mouse along with the ability of three representative mAbs to induce nephritis in nonautoimmune mice using established adoptive transfer protocols. One monospecific anti-single-stranded (ss) DNA (11F8) induces severe diffuse proliferative glomerulonephritis in nonautoimmune mice whereas another anti-ssDNA with apparently similar in vitro binding properties (9F11) and an anti-double-stranded DNA (4B2) are essentially benign. These results establish a murine model of anti-DNA-induced glomerular injury resembling the severe nephritis seen in lupus patients and provide direct evidence that anti-ssDNA can be more pathogenic than anti-double-stranded DNA. In vitro binding experiments using both protein-DNA complexes and naive kidney tissue indicate that glomerular localization of 11F8 may occur by recognition of a planted antigen in vivo. Binding to this antigen is DNase sensitive which suggests that DNA or a DNA-containing molecule is being recognized.


Antibodies, Antinuclear/genetics , Antibodies, Antinuclear/immunology , Antibodies, Monoclonal/genetics , Antibodies, Monoclonal/immunology , DNA/immunology , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , DNA/genetics , DNA Primers/genetics , Genes, Immunoglobulin , Hybridomas/immunology , Immunoglobulin Variable Region/genetics , Kidney/immunology , Kidney/pathology , Ligands , Lupus Nephritis/etiology , Lupus Nephritis/genetics , Lupus Nephritis/immunology , Mice , Mice, Mutant Strains , Microscopy, Electron , Molecular Sequence Data , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid
9.
Biochimie ; 75(6): 433-41, 1993.
Article En | MEDLINE | ID: mdl-8364093

Inverted repeat sequences derived from the ColE1 cruciform were investigated by nuclear magnetic resonance (NMR) and UV spectroscopy. It was shown that 15 different sequences exist as stable hairpin structures over a range of buffer conditions and DNA concentrations. Experiments with six oligomers (1-6) containing the native stem sequence and five base loops, found that the two hairpins with the wild-type loops (1-2) served as upper and lower bounds for the thermodynamic stability of all the other sequences. NMR experiments, including rotational correlation time measurements and NOESY spectra, were then performed on 1, the most stable hairpin sequence to begin to uncover a structural basis of its stability.


Bacteriocin Plasmids/chemistry , DNA, Bacterial/chemistry , Nucleic Acid Conformation , Base Composition , Base Sequence , Drug Stability , Magnetic Resonance Spectroscopy , Molecular Sequence Data , Repetitive Sequences, Nucleic Acid , Spectrophotometry, Ultraviolet , Thermodynamics
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